A lonely husband is quite often lonely because of a lack of intimacy with his wife. Most often the trouble begins when the husband starts to take his wife for granted.
...his job. When he gets home he does not have enough energy to live life itself.
He relies on his wife to provide cooked food, the comforts of home and sex. He feels that because he provides the income, everything else is his wife's responsibility. He forgets that entertainment and good times are some of his major responsibilities even after bringing home an income. In two income homes, the husband quite often behaves as if he is the sole income provider.
Instead of his wife being the center of his world, she is barely at the edges of his world. His world seems to consist of work, sports, computer games, alcohol and rest. He seems to let his wife into his world only when he wants sex.
Sometimes it is the husband at fault - he disconnects emotionally from his wife and his wife has no clue why he has drifted away from her. She may not even realize that her husband is lonely. All she knows is that her husband is emotionally unreachable.
...a few months or years after the couple has taken the marriage vows. If the wife is not happy with the real personality of the man she married, communication between the couple could break down, causing loneliness for both.
If a husband loses his temper very easily or is in a bad mood most of the time, his wife tends to leave him alone and walks around on egg shells in his presence. Pretty soon his wife's emotional needs are being met by someone else. The husband is incredibly surprised when he finds himself alone and lonely. Infidelity by a wife can cause terrible loneliness for a husband because it destroys the substance of the marriage while leaving the shell intact.
...the emotional needs of his wife. He is also unaware of the mental make up of women in general. It seems men don't understand women well and on top of that they tend to take their wives for granted.
The way for a husband to start understanding women is to read the book, "Men Are From Mars, Women Are From Venus" by John Gray. Then he might want to search out and read books which will give him an insight into the minds of women.
...when he gets more insight into the minds of women, the first thing a lonely husband will do is stop taking his wife for granted.